Omega-3 highly unsaturated fatty acids (HUFAs) are of significant commercial interest in that they have been recently recognized as important dietary compounds for preventing arteriosclerosis and coronary heart disease, for alleviating inflammatory conditions and for retarding the growth of tumor cells. These beneficial effects are a result both of omega-3 HUFAs causing competitive inhibition of compounds produced from omega-6 fatty acids, and from beneficial compounds produced directly from the omega-3 HUFAs themselves (Simopoulos et al., 1986). Omega-6 fatty acids are the predominant HUFAs found in plants and animals. Currently, a commercially available dietary source of omega-3 HUFAs is from certain fish oils which can contain up to 20-30% of these fatty acids. The beneficial effects of these fatty acids can be obtained by eating fish several times a week or by daily intake of concentrated fish oil. Consequently large quantities of fish oil are processed and encapsulated each year for sale as a dietary supplement. However, there are several significant problems with these fish oil supplements, including bioaccumulation of fat-soluble vitamins and high levels of saturated and omega-6 fatty acids, both of which can have deleterious health effects.
Another source of omega-3 HUFAS is the microflora Thraustochytrium and Schizochytrium which are discussed in detail in related U.S. Pat. No. 5,130,242. These microflora have the advantages of being heterotrophic and capable of high levels of omega-3 HUFA production. There still exists a need however for improved methods for fermentation of these microflora and identification of improved uses of the microflora product.